An adjustable socket that can fit varying sizes of fasteners (nuts, bolts, etc.) can replace several fixed-size sockets, reducing the components of a socket set into a minimal number of tools. An adjustable socket allows for streamlining of workflow, as time is no longer spent finding and selecting the correct fixed-size socket from a set. An adjustable socket may also more tightly grip a damaged or worn fastener than a fixed-size socket.
Several adjustable sockets exist in the prior art which are manually adjustable to fit varying sizes of fasteners, by means of a plurality of jaws which are moveable along a fixed path. However, despite the basic functionality of these devices, they are susceptible to inherent design restrictions that limit their effectiveness and range of operation.
The operating range of an adjustable socket with jaws whose pathways travel in a direct radial path toward the fastener is inherently limited. To allow for a wider direct radial contraction of jaws on the head of a fastener, these devices must either have a limited number of jaws, or jaws much narrower than the faces they are intended to grip. These conditions result in decreased shared surface area between the sockets and fasteners, which results in reduced force potential and increased slippage.
In U.S. Pat. No. 8,893,592, there is disclosed an adjustable socket that is manually operable by means of a drive core, which moves jaw members along fixed paths oblique to the center of the socket, and is locked in place by a biased indexing collar. Although this socket allows a user to grip hexagonal fasteners of a wide range of sizes, the features designed to restrict unwanted movement of the jaws are not sufficient, and the drive interface between drive core and jaws restricts the range of available locking sizes for the unit.